Understanding the code

Rudrabhadra 

GetOpenFileName with MultiSelect:=True can return two completely different types of values:

• If the user selects one or more files and clicks Open, it returns an array of string values. Each item of the array is the path + filename of one of he selected files. VarType(fNameList) will be vbArray+vbString.
• If the user clicks Cancel, it returns the Boolean value False. VarType(fNameList) will be vbBoolean.

So the line If (vbBoolean <> VarType(fnameList)) Then checks that fNameList is not a Boolean, i.e. it must be an array.

The next line If (UBound(fnameList) > 0) Then will only be executed if the user clicked Open. It checks that the fNameList array has more than 0 items. This line is actually not necessary, if the user clicked Open they have selected at least one file.

I assume that the code below that loops through the selected file names, opens each workbook in turn, then loops through the sheets of the workbook. The lines

            countFiles = 0

            countSheets = 0

initialize the count of files (workbooks) and of sheets to 0.